As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMBING THROUGH FLIGHT LEVEL 380 WITH THE AUTO PILOT ON AND FLIGHT LEVEL CHANGE SET TO .65, THE ACFT PITCHED UP TO APPROX 10 DEGREES. THE VERTICAL SPEED INDICATED A CLIMB OF OVER 3000 FT PER MINUTE. ACFT LOST 18 KNOTS INDICATED AND STARTED TO EXPERIENCE BUFFET. DISENGAGED THE AUTOPILOT AND RECOVERED ACFT. AUTOPILOT SYS OPS TEST IAW MM 22-11-03. NO FAULTS FOUND.